What happened in 1998?Harry Potter and the Chamber of Secrets (Book 2) was pulished in the U.K.
in July of 1998, and was a runaway bestseller.

A few months later, Americans
finally got their copies of Book 1, now titled Harry
Potter and the Sorceror's Stone; they (and other fans outside the U.K.) were immediately hungry
for more, and had to resort to purchasing Book 2 from British bookstores,
as it didn't come out in the U.S. until the summer of 1999.

Face to Face with J
K Rowling: Casting a spell over young minds
The
Herald (Glasgow)

JKR: "To invent this wizard world, I've
learned a ridiculous amount about alchemy. Perhaps much of it I'll
never use in the books, but I have to know in detail what magic can
and cannot do in order to set the parameters and establish the stories'
internal logic."

JKR: "the books do explore the misuse
of power, and there's an attempt to make some sense of death"

JKR: "it's indecent the amount of time
I spend thinking up wizarding ways to subvert arrogant Muggles."

Difference between charms and transfiguration?
JKR: "With a charm you add properties to something. With a transfiguration
you change its nature completely; the molecular structure alters..."